Thermotic switch.



G. P. HUMPH'REYS.,l

LTHERMOTIC SWITGH. APPLICATION HLEDMAR. s. 1912,'

1,042,920. Pmtedut. 29, 1912.

wi/Mimmo v v i 33,1, mw

UNITED STATE-s GUY n. HUiviPHnEYs, oF DEVIVLs naamw@ Assrenonrdo. E. n-UBGESS..

ornEvILs LAKE,

PATENT torsion.

pongan. DAKOTA.

'rnnmixorrcy ,swrajcrf specificationof'` LettPP ilfilatented Uct.f29,1912ix Application mea March s, 19112; serial no. 632,361.,

l'o all whom it may concern: l

lle 1t known that I, GUY F.. HUM'PHREYS,;

a Citizen of the United States, residing at Devils Lake, in `thecounty of Ramsey and State of North Dakota, have invented certainnew and useful Improvements in Ther motie Switches, of whichthe following is' a` specification.

The present switch-1s 'of the thermotic 4type and comprises essentially a device tobe connected to apartwhich, in use, is heated, the'l switch operatingto close ay circuit only when the-supportingV part has become so hot as to create anger, give rise to possibility of injury thereto, or cause defective or in'- efiicient operation;

The 'invention involves primarily the peculiar construction of the thermotic switch, the same being simplified so as to permit of ready assemblance of its,` various parts, and access thereto underpractical conditions of F or-afullu'nderstanding of the present' invention, reference is tobe had' to the following description and to the accompanying Vdrawings, in which* tical-Sectional 'View'.` Fig. Bis a viewloking down upon themercury reservoir, the

parts above the plu being omitted.

Throughout the ollowlng detaill description and on'fthe'several figures of the draw-y ings, similar parts arereferred to by like4 reference characters. Y

Describing the invention specifically,l denotes a reservoir made of conductive matel.

rial suchy as any suitable metal'and adapted ,to be attached atits base portion l. 'tov a, hotboinjengine cylinder, or any equivalentl device-which, in its ordinary use, 1s sub-"f jected to more or less heat. f

The reservoir 1 is of somewhat cylindrical yshape preferably and it is adapted to'contain'a small quantity of mercury, as shown in the drawings.. The upper portlon of the interior of the reservoir is enlarged somewhat so as to receive a plug 2, the lower end of which is seated on the shoulder formed by the lower extremity of said enlarged portion. The plug 2 is formed With'a central f narrow orifice 3,.tiie ul'gp'er portion of which lcoinmuniCates with a recess'ffleading down-v wardlyifrom the up forming a shallow basin or pocket.

nally threaded tol receive la screw cap 4, the latter being formed with av knurled flange 4; to facilitate rotation thereof,l and also with a central opening having an offset portion 4f at itsV inner extremity. Through the 'central openingof the cap Ltpasses an insulating tube 5 formed with a iiange 5 at its lower extremity. A, contact rod 6 passes through thetu'bular Aportion of the insulating tube 5 and basa clamping nut 7 screwed screwed on its upper portion. The lower extremity 6 of the rod 6 is taperedto af contact point, and a metallic capmember 9 is sulating tube 5.

vquantity of mercury 'is'contained by the circuit wires are connectedwith the switch, one wire being preferably secured thereto by being clamped between the parts 8 and 9 and the other wire is attached to a art of the device electrically connected wlth 'the reservoir l.. As shown, the last mentioned wire is secured by a screw to the capl.

lIt will be apparent that the cap 4s holds the plug 2 in place in the reservoir l, and in addition, said cap fir1nly clamps thein'- sulating tube 5 in position on the device by engaging with` the `iange 5f of said tube and holding said fiange in abutting relation to the plug 2. The contact point 6 of the rod 6 with the partsl arranged as above de scribed, is located in thebasin or pocket 3 of the plug 2 and in the actual use of the device, when the part to which the switch is ydegree, the mercury in the chamberA will rise through thel orifice 3 and enter the cludin'g the wires electrically/connected yto the parts 6 and l is closed and an alarm or signal, not shown, in said Acircuit will be is detached from .the'reservoir 1 Aand the parts 8 and 9 unscrewedv from the *rod 6.

Furthermore, anice adjustment ofthe conper lsidey vofthe plug At its upper end,'the`reservoir l is inter` seated over the upper extremity of the in-l In thev operation of the invention, a small on its lower end portion and a binding nut 8 Y chamber A ofthe reservoirl and electric attached is heatedbeyond a predetermined -loj pocket 3. As'soon as the mercury'con-U tacts with thecontac't point 6, the circuit insounded, The insulating tube 5 is readily removable from .the cap 4 whenv the lat-ter` 11ol f y tact point 6 in relation to the orice 3 may be readily obtained by manipulation of the clamping nut 7.

Having thus described the invention, What is claimed as new is:

l. A thermotic switch of the class described comprising a reservoir. provided With a mercury chamber and an enlarged' portion above said chamber, a plugedisposed in said enlarged portion and provided with an orifice communicating with the mercury chamber, a screw cap carried by the reservoir and engaging said plug to hold, the

same in place, an insulating tube passing through said screw cap and clampedjthereby against the plug, a contact rod supported by said tube and having a contact point adjacent to the orice in the plug, and circuit. Wires electrically connected with said rod and with the reservoir. y

2. A thermotic switch -of the class described comprising a reservoir provided with a mercury chamber and an enlarged internal portion above said chamber forming an annular shoulder, a plug received-in the upper portion of the reservoir and seated against said shoulder at one end, a cap screwed into the upper end of the reservoir and abutting with said plug to hold the saine in place, said cap having an opening,

.Sulating tube passing through the cap and formed with a iiange received by the enlarged portion of the opening in the cap and-'abutting also with the plug, a contact rod passing through the tube and having a contact point at its inner end adjacent to said orifice, a clamping nut applied to the inner portion of said rod and located at the inner end of the insulating tube, a binding nut screwed upon the outer end portion of the rod, and circuit Wires one owhich 1s electrically connected to the reservoir and .the other of which is connected to the contact rod by means of .the clamping nut.

In testimony -whereof I aix my signature in presence of two Witnesses.

GUY F. HUMPHREYS.

Witnesses:

C. E. BURGESS, ELLA A. Bnncnss.

e #Commissioner of Patents.

,the inner end of which is enlarged, anvin- 

